The present invention relates to a front deflector for a mower having discs driven from beneath.
Mowers of this type especially comprise a elongated housing containing the transmission elements serving to drive in rotation the discs situated above this housing, which is of minimum possible depth so that the cutting elements of the discs may cut the fodder as close as possible to the ground. Despite its shallowness this housing must have great rigidity with the purpose of ensuring good working of the said transmission elements. The manufacture of such a housing causes no problems for mowers having a working width less than 1.80 metres. However it is necessary to provide a device ensuring rigidity of the housing in disc mowers having a working width greater than 1.80 meters. meters.
For this purpose this latter type of disc mower is advantageously provided with a device comprising a beam extending above the discs and connected to the end of the elongated housing. At the end nearer at least one end of said housing, that is nearer to the outer disc this beam is connected to the said housing by means of an arm. The presence of this arm, generally fixed in the sector swept by the rear outer part of the outer disc of a mower, nevertheless constitutes a significant obstacle to good working of the mower provided with it. In fact in order to facilitate the separation of the cut fodder from the standing crop material, numerous disc mowers are provided on their outer disc, with a member such as a truncated cone, or equivalent members which also move the cut fodder rearwardly. These members perfectly fulfil their function on mowers not provided with the device intended to ensure rigidity of their housings. But, when an arm is situated close to the outer disc of a mower provided with a beam ensuring rigidity of its housing, the fodder which moves rearwardly for example thanks to a truncated cone tends to accumulate at the level of the said arm. This fodder is then minced in the subsequent passages of the cutting elements of the outer disc of the mower in the vicinity of this arm. This accumulation of fodder can even in certain cases jam the machine when the clogging effect becomes too great, and in all cases compels the user to stop the machine frequently to clear the fodder thus accumulated. Moreover, especially when the machine is cutting particularly tall and dense fodder, the outer disc, surmounted by its truncated cone, no longer succeeds in conveying the whole of the fodder towards the rear of the machine for the purpose of its deposition on the ground in the form of a windrow clearly separated from the still standing fodder. A certain quantity of cut fodder is then deposited in the zone situated between the still standing fodder and the windrow formed by the mower, whereas this zone, reserved for the passage of the tractor wheels, should normally be free of all fodder. There is thus poor separation between the mown fodder and that still standing. In the subsequent passage of the machine there is danger then of a part of the mown fodder being crushed by the tractor wheels, or being cut afresh by the mower, which then causes mincing harmful to the quality of the said fodder.
This drawback is remedied to a certain extent by increasing the height of the truncated cone fast with the outer disc. This solution is also unsatisfactory since such a rotating element, of significant height, can rapidly impart a significant unbalance. This significantly reduces the life of the bearings on which the outer disc of the mower is mounted, since these bearings are more greatly stressed than if the outer disc were equipped with a shallow truncated cone.
The object of the present invention is the provision of a front deflector adaptable to disc mowers where the elongated housing is associated with a device intended to ensure its rigidity, this deflector remedying the above-stated drawbacks. This deflector, which ensures a quite clear separation between the already cut fodder and that still standing, avoids the phenomena of clogging and mincing. This deflector likewise co-operates effectively with an element of known type, for example of shallow frustoconical form, mounted on the outer disc.